Inverted piston pump



Dec. 13, 1938. C, ROKKJAR 2,139,972

INVERTED PISTON PUMP Filed June 25, 1937 2 Sheets-Sheet l #4T Chn'lgtytykjar c. ROKKJAR 2,139,972

INVERTED P I STON PUMP Filed June 23, 1937 2 Sheets-Sheet 2 Ow I6ATTORNEYS Patented` Dec. 13, l1938 UNITED srArEs rArENr orifice l 2.13ammvanrnn rr's'roN PUMP christian maar. sam Woolley, Wash. Appuuon Juneze, 1931, semi No. 149,967

. 3 Claims.

My present'invention relates to huid pumps and more particularly to aninverted piston Pump- There are many types of pump constructions,especially forl pumping water, available on the market. These, however,are characterized by either providing pumps that are constructed tooperate reciprocating pistons, v'that' operate on1 the centrifugalprinciple, or pumps that may be generally classed as gear, or rotor,pumps. Each of these requires careful machining and unless they areofthe more expensive type using Vmultiple units Lthey cannot be dependedupon to supply a uniform ilow of liquid. The controllingv factor thatmakes these pumps expensive in manufacture is the requirement ofaccurate machine work@ -and the fact that they are normally intended towork against considerable head. In my present invention, however, I amendeavoring to supply 2l) the demand for pumps that will work againstonly a nominal head and, as a result, I am able to provide a pump having-a short stroke and a moderately large bore. This form of constructionlends itself to economical manufacture. It 26 is no longer necessary tohave a crank to reciprocate the piston. The valving arrangement A, canbe greatly simplified and the'f short stroke permits the use ofeccentrics for reciprocating the pistons which in my present design arearranged to rockin the cylinders, due to their slight angulardisplacement, instead of being con- `nected to a crankshaft by theconventional connecting rod-` or cross head assembly which is requiredwhen the piston reciprocates in the l normal manner.

I further provide in my present design a very simple constructionwherein the piston assembly, or assemblies, in a multi-cylinder unit isdisposed in the lower part of my pump chamber and as the water is drawnthrough the piston into the chamber it. has at all times a volume of airthat is compressed above the water so as `to provide an air dome thatwill equalize the pressure and maintain a substantially even iiow on theoutlet 45 or discharge line.

Other and -more specic objects will be apparent from the followingdescription taken in connection with the accompanying drawings, wherein-Figure 1 is a longitudinal vertical section through a pump made afterthe teachings of my present invention. Y. A j

. 'f Figure -2 is a cross-sectional` view' through one cy1inder'-of.thepump shown in Figure 1, '55 the cutting plane being taken at rightangles to that gure.' ,l

. Figure 3 isA a side elevation of my pump Show,-

ing the same as connected to an electric motor.

Figure 4 isf a cross-sectional view cothelinel-lofrlgurel.

(el. ros-1am' w i Figure 5 is a cross-sectional view taken along theline B-B of Figure i.'

Figure 6 is a cross-sectional view taken along theline 6--8 of Figure l.

Figure 7 is a cross-sectional view taken along the line i--l of Figurel.

Referring to the drawings, throughout which' like reference charactersindicate like parts, 8 designates the upper pump chamber which is.adapted to be xedly secured 'as by bolts Il! to the base housing I2.Secured between housing members 8 and I2 is the cylinder unit I. Thisunit'is entirely separate from members 8 and I2 and may be supplied toaccommodate any reasonably desirable number of pistons. vThroughout thepresent drawings I have shown a threecylinder unit.` It is believed itwill be apparent that if only the capacity of a one-cylinder pump isneeded, only one such piston assembly would beV l employed. If it isnecessary to increase the capacity twoor more cylinders might be used orif desirable therentire housing 8 and I2 might be lengthened to provideany reasonable number of cylinders.

Each cylinderas I6 is provided with relatively short walls and hasdisposed in the lowerk'portion a plate or disc valve I8. This valve isurged, by spring 20, to cover a plurality of openings as 22 and thusprovide the intake valve for my -pump cylinder. Disposed within cylinderI6 is piston proper 2l. This member is provided with a rela-- tivelyshort skirt which is used to seat a exible cup washer 26. This cup maybe made of any suitable material, which should necessarily be selectedin accordance with the uid to be pumped; for water a leather orcomposition cup is' probably most desirable. v

To further assure an even ow of water into .the intake`valve chamber Iprovide that the intake valve itself be placed at the extreme bottom ofthe cylinderv member I6 and,- as no provision is made to fully exhaustthe air from the chamber below bame Il, a certain amount of air will betrapped there whichA will function as an air. dome. This, under certainconditions of use, isvery desirable and with a single cylinder unit it\is necessary that a greater air volume be provided. This in my presentarrangement isautomatically` assured' in that, if only one cylinder isused, `there will be a large volumeA below baille M'; and, as eachadditional cylinder is installed, there will be acorresponding-reduction in the volume of this lower chamber'.` Flx'edlysecured to piston 24 is piston rod 28. This rod is'probably bestillustratedin Figures 1 and 2. It is belled out at its lower end so asto provide o'ne of the seat members for the cup 26, .it being preferablythreaded, or otherwise secured, to the lower piston member 24. l Thispisv ton memberif provided with a valve quite similar go to valve I8 inthat it has a plate or disc 28, of suitable material, which is adaptedto cover openings 30, in member 24, and is urged into its closedposition by spring 32.`

The upper end of piston rod 28 is provided with a circular bearingportion 34 in which is disposed a suitable, preferably, fibrous bushing36.

. operatively engaging bushing 66 is eccentric 88.

This member should be preferably of a rustproof or stainless materialsuch as Monel metal or stainless steel, or somelof the various bronzebearing alloys. The eccentrics arev secured as against rotation on shaft48 by any suitable means. As at present constructed I prefer to use aWoodruff type of key 4I, in the left hand eccentric as viewed in Figures1 and '1, and to suitablysecure the other eccentric to this one by somecdnvenient means. In Figure 2 and particularly in Figure 7 I have shownthis as accomplished by using dowelV pins as 4Ia. It will be apparent itis believedthat other suitable keying means might be previdedor'theabutting faces of the different ecceitrics might be deformed so that themembers would engage in locked rela# tionship.

Inasmuch a's the' pump is designed to operate against low pressuresthere is no objection to having a relatively large area to piston 24,consequently, the stroke can be. reduced to'a point where eccentricoperation is satisfactory.- Shaft 40 is provided with a Journal at oneend in bushing 42 and. at its other end, which must take the belttension, it; is provided with preferably an antifriction bearing capableof carrying in addition to the radial loading a certain amount of thrustloading. 'I'he roller type of bearing shown at 44 has been found to bevery satisfactory. This bearing is best supported, as indicated, inaseparate collar 46 which while normally formed in the same casting withhousing 6, is spaced therefrom as by the spider. arrangement 48 so thatpacking can be renewed and adjusted and any leakage that^might passthrough packing l and packing gland 5I will be dissipated down the sideof vhousing 8 and will not enter the bearing housing which 'must `ofnecessity be protected as by vlubricant retainers 53 and54. A furtheradvantage of this construction is that packing gland nut 5| is readilyreached for adjustment or for `the replacement of packing ll. It isdesirable, if a roller bearing is used as is indicatedv inFig'- ure 1,that the bearing be so placed as tol take thrust from the pumpcavityasit will be apparent that theLpressure built up within the pumpwill be applied to the end bushing 56, secured to shaft 48;' when thebearing is so placed it will be properly 'seated by the pump pressurewhich further tends to seat the various units in a xed relationship withone another.

. In order to effect an easily assembled unit I provide iirst that shaft40 be threaded or otherwise secured within a bearingl member 66, theoutside diameter of which is the body size of the spacer bushing onshaft 48. Bearing I6 is .in

turn Journaled within bushing 42. lIt has been eccentrics and at thesame time it expels the short shaft which will pass out through theopening providedcfor packing 50. It will be seen from Figure 1 that theheight of'key 4| does not exceed the height of the spacers or bushings58 that are disposed' upon shaft 40. When the eccentrics are inplaceeach surrounded of course by itsl piston yrod 28, bushing 58 isinstalled, then bearing 44 and nally after the lubricant retaining rings53 and 54 are screwed in place, y wheel 60 is placed on the shaft andsecured thereon as by nut 62. Tightening this nut forces all thebushings and eccentrics against bearing 44.

As an -aid in assembling the unit I provide that the discharge opening.will be at 64 co-axially with -shaft 40 and of a suflicient size so thatthe shaft bushings can pass therethrough. I'he intake of the pump isprovided at 66 where the fluid entering the pump then passes up throughthe screen 68. It will be understood, it is believed, that any suitablesource of motive power might be employed. In Figure 3 I have shownA 1.AIn a liquid pump, the combination withvan upper casing, a base, anintermediate partition having an integral annular series of open-topported cylindersprojecting. on diagonal lines, exterior tie boltsconnecting said base and casing and spring-pressed valves` in saidcylinders, of a rotary shaft journaled in the casing and a series ofstems eccentrically mounted thereon, sad stemseach having a hollow headand a ported f'piston mounted in said head a spring-closed valve foreach piston,and said pistons being oscillatable and reciprocable in thecylinders.

2. In-a liquidvpump the combination with a pump casing and its rotaryshaft, an .end bearing foi` the shaft in one wall of the casing andoutlet Aports adjacent said bearing, a packing nut in an oppositewallfor said shaft, an exterior Ispiderframe rigid with the latter walland a bearingcollar rigid with the frame, a bearing for the shaft withinsaid collar, and closures for said bearing at the opposite'ends of thecollar.

3. Ina liquid pump, the combination with a hollow base having ascreened-bottom-intake, an upper casing having a central lateral butlet,an

intermediate partition having an annular seriesv CHRISTIAN ROKKJAR. u

